According to a study, dogs are able to tell lies. Here is the interesting experiment!
Some owners have suspected this for some time, but now the confirmation has come from scientific research, which has shown that even dogs are capable of engaging in deceptive behavior.
The study investigated whether dogs were able to mislead a human competitor in a choice situation. During training, the dogs had to deal with their owner, cooperative, and with two strangers: one who acted cooperatively, giving food to the animal, and the other competitively, keeping the food for themselves.
Dogs tended to guide the human competitor away from the food when they thought that man would keep him for himself. Instead they happily took their co-op mate to their destination, knowing they would receive some of the food. During the test, the dog could lead one of these partners to one of three food positions: one contained the preferred food product, a second a non-preferred food product and a third was empty.
After leading one of the strangers, the dog could lead its cooperative owner to one of the locations. Therefore, the dog would have a direct advantage in deceiving the competitive partner as it would then have another chance to receive the owner's favorite food. This is exactly what the animals did, thus showing that dogs distinguish between cooperative or competitive behavior, adapting their behavior also using deception.